(AP Photo/File). FILE - A Dec. 1, 1981 file photo shows actress Natalie Wood. Investigators are now calling 87-year-old actor Robert Wagner a "person of interest" in the 1981 death of his wife Natalie Wood. Mystery has swirled around Wood's death. It w...

(AP Photo/Paul J. Harrington, File). FILE - This Nov. 30, 1981 file photo shows the "Prince Valiant," the inflatable dinghy used by Natalie Wood, moored at the harbor in Avalon, Calif., after it washed up on the rocks on Santa Catalina Island. Patrolme...

(Photo by Todd Williamson /Invision/AP). FILE - In this Dec. 1, 2013 file photo, Robert Wagner attends The Caucus for Producers, Writers and Directors 31st Annual Awards in Beverly Hills, Calif. New witnesses have emerged in the 1981 drowning of actres...

By MICHAEL BALSAMOAssociated Press

LOS ANGELES (AP) - Detectives hope the renewed interest in the mysterious 1981 drowning death of actress Natalie Wood will bring forward new witnesses who provide the information needed to determine if the case was a crime or tragic accident. If not, it may be the end of the investigation, a Los Angeles County sheriff's official said Monday

For nearly four decades, speculation has swirled around the death of the 43-year-old actress who was nominated for three Academy Awards and starred in "West Side Story" and "Rebel Without a Cause." She was on a yacht with her husband, actor Robert Wagner, actor Christopher Walken and the boat captain on Thanksgiving weekend of 1981. After a night of drinking, her body was found floating in the waters off Southern California's Catalina Island.

Investigators initially ruled her death as an accidental drowning. But the case was reopened in 2011 to see whether Wagner or anyone else played a role after the boat's captain said he heard the couple arguing the night of her disappearance. The coroner's office later amended Wood's death certificate to include "drowning and other undetermined factors."

Detectives have reclassified Wood's drowning as a "suspicious death" and say Wagner is a person of interest in the case. But the evidence collected so far hasn't reached the threshold for a murder investigation and there are no immediate plans to file criminal charges, detectives said Monday.

Several new witnesses have come forward since the case was reopened, including one who described hearing yelling and crashing sounds coming from the couple's stateroom, officials said. Shortly after that, separate witnesses who were on a boat that was in the water nearby, heard a man and woman arguing on the back of the boat and believe the voices were those of Wood and Wagner, according to detectives.

Those witnesses corroborated the account of the boat's captain, Dennis Davern, who had told detectives he heard Wood and Wagner arguing in their cabin on the boat and went to check on them. When he went to their cabin, Wagner told him to go away before Wagner and Wood ended up arguing on the back of the boat, sheriff's homicide Lt. John Corina said Davern told investigators.

"He was the last person with her, arguing, before everything went quiet," Corina said of Wagner. "He's a person of interest because he was the last person with her before she went in the water."

Wagner only spoke to detectives after the drowning in 1981 and although investigators have tried to question him several time since they reopened investigation, he has refused, Corina said.

Wagner's initial statement about what happened and subsequent comments about the case "really don't add up to what we found," Corina said.

Wagner has denied any involvement in Wood's death and his attorney has said he fully cooperated with investigators.

The actor's publicist, Alan Nierob, said detectives have not contacted Wagner, now 87, in more than five years but declined to comment further on the case. Sheriff's officials would not say Monday when they last tried to contact Wagner.

Time has been the largest obstacle in the probe and the original investigator and many of the witnesses have died, Corina said.

"We're doing our last shot here, seeing if anybody else comes forward with any information," he said. "When the tips all dry up, then I guess we move on to the next case."

Florida Gov. Rick Scott is vowing to do what he can to keep mentally ill people from getting guns. Attorney General Jeff Sessions also is focusing on intervening with mentally ill people before school shootings happen.

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